CLAS physics database search results Measurement E151M1649 EG4 Xiaochao Zheng 2016 cos(theta_pi+) phi(pi+) A_LL Stat. error Syst. error degrees 0.65 210 1.4996 0.8916 0.0922 0.65 222 -2.3326 0.5403 0.1389 0.65 234 0.4406 0.9845 0.0394 0.65 246 0.4973 1.0372 0.0417 0.75 210 -2.536 2.536 0.1505 0.75 222 -0.8481 1.0367 0.0577 0.75 234 -1.0853 0.981 0.0699 0.85 222 0.8371 1.1215 0.0572 0.85 234 1.4477 0.8341 0.0894 0.85 246 -0.336 0.9957 0.0358 0.35 42 1.0225 0.906 0.0682 0.55 234 -0.122 0.9536 0.0309 0.75 210 0.4921 0.9382 0.0421 0.75 222 -1.0293 0.9096 0.0686 0.75 234 -0.6039 0.8943 0.047 0.85 138 -0.2607 0.9672 0.0338 0.85 210 0.685 0.8809 0.0508 0.85 222 -0.5089 0.8657 0.0428 0.85 234 0.6841 0.7639 0.0508 0.85 246 1.3357 0.8446 0.0855